(湖南大學 材料科學與工程學院，長沙 410082)
摘 要: 采用Bc路徑對超高強鋁合金基復合材料7090/SiCp進行等徑角擠壓加工。采用金相顯微鏡、力學性能測試及掃描電鏡，分析該復合材料的顯微組織和力學性能。結(jié)果表明：經(jīng)過4個道次的等徑角擠壓加工，該復合材料的晶粒逐漸被細化，第三道次后晶粒尺寸達到1 μm以下；繼續(xù)進行等徑角擠壓時，晶粒未發(fā)生明顯變化。室溫拉伸結(jié)果顯示：晶粒的抗拉強度逐漸增大，在第三道次下道次間抗拉強度的增加幅度最大，達到14.3%，此時其抗拉強度及伸長率分別為338.57 MPa及15%；SiC顆粒在大的剪切力作用下被破碎細化，在基體中的分布也更加均勻。
關(guān)鍵字: 鋁基復合材料；SiC；等徑角擠壓；顯微組織；力學性能
（College of Materials and Engineering, Hunan University, Changsha 410082, China）
Abstract:The structures and properties of 7090/SiCp Al matrix composites were studied by severe plastic deformation through Bc route equal channel angular pressing (ECAP). Equal channel angular pressing was performed on an ultra-high strength 7090/SiCp aluminum alloy matrix composite. By optical microscopy, mechanical tensile test and scanning electron microscopy, the microstructures and mechanical properties of 7090/SiCp composite were discussed. The results show that the size of the composites is fined gradually, and the finest grains are obtained of less than 1 μm after 3 passes of ECAP. However the grains do not change after the 4th pass of ECAP. The tensile strength increases gradually with the addition of pass at room temperature, and the increasing degree between two passes achieves the maximum at the third pass, is 14.3%, and the ultimate tensile strength and elongation are 338.57 MPa and 15%, respectively. SiC particles are broken under high shearing stress, and the particle distribution in the matrix alloy is homogeneous.
Key words: aluminum matrix composite; SiC; equal channel angular processing; microstructure; mechanical properties
ISSN 1004-0609
CN 43-1238/TG
CODEN: ZYJXFK
ISSN 1003-6326
CN 43-1239/TG
CODEN: TNMCEW